1. Field of the Invention
This invention relates to improvements in high temperature industrial furnaces. More particularly, this invention relates to a removable toe portion for a suspended refractory shield for a high temperature industrial furnace.
2. Description of the Prior Art
Suspended refractory shields for high temperature furnaces and the importance of cooling of metal hangers supporting the refractories in such construction is known, such as taught by U.S. Pat. No. 3,812,798. Suspended refractory wall construction frequently involves turns or nose constructions which have their center of radius outside the cold side of the furnace, such as in the bottom of a feeder wall. Prior such construction, as shown in FIG. 2 of U.S. Pat. No. 3,812,798 have a fixed curved hanger portion from which the refractories are suspended with the necessity for a spring biased plate to urge the refractories forming the curved portion upwardly to maintain their position and to accommodate temperature changes during furnace operation. Frequently, the toe portion of the refractory shield is at the location of intense heat and in contact with batch constituents which cause deterioration requiring replacement of the extreme lower refractories of the curved structure. In order to replace the lower refractories of the curved structure as shown in FIG. 2 of the U.S. Pat. No. 3,812,798, it is necessary to disassemble the entire length of the curved structure from the inside of the furnace.
The desirability of replacement of refractories from the cold side of curved nose construction in high temperature furnaces without disassembly of the entire length of the nose construction is taught in U.S. Pat. No. 4,463,689. The U.S. Pat. No. 4,463,689 does achieve the ability of replacement of a small number of refractory bricks from the cold side of the high temperature furnace, but cannot be used in the refractory wall system providing for direct fluid cooling of the metallic hangers.